Searching for Spaceships
Abstract
Description
We describe software that searches for spaceships in Conway's Game of Life and related two-dimensional cellular automata. Our program searches through a state space related to the de Bruijn graph of the automaton, using a method that combines features of breadth first and iterative deepening search, and includes fast bit-parallel graph reachability and path enumeration algorithms for finding the successors of each state. Successful results include a new 2c/7 spaceship in Life, found by searching a space with 2^126 states.
17 pages, 13 figures. This revision adds Paul Tooke's new c/6 "dragon", and corrects one URL. For more information about the software and patterns described here, see http://www.ics.uci.edu/~eppstein/ca/
17 pages, 13 figures. This revision adds Paul Tooke's new c/6 "dragon", and corrects one URL. For more information about the software and patterns described here, see http://www.ics.uci.edu/~eppstein/ca/